Calcium cyanamide fertilizer compositions and methods for their use are disclosed. The compositions and methods stabilize active ionic compositions comprising calcium cyanamide and enhance the effectiveness of calcium cyanamide alone or synergistically in combination with nitrogen containing materials such as urea and organics, for example, manures. The compositions and methods also facilitate controllable site directed delivery of the contents of the stabilized compositions. The compositions and methods are effective for fertilizing, soil amending, metal stabilizing and odor and organism inhibition. The compositions are stable, easily calibrated, and non-clogging for spray delivery to target sites.